1. Technical Field
The present invention relates to a motor drive circuit, a printing apparatus, and a semiconductor device.
2. Related Art
In recent years, various motors are used in electronic apparatuses for various purposes. For example, in a printer, a motor is used for moving a carriage on which a cartridge is mounted or for transporting a printing paper.
In order to use a motor, a motor drive circuit which drives a motor is needed. For example, JP-A-2012-178948 discloses a motor drive circuit which uses an H bridge circuit. In the motor drive circuit, driving control of a motor is performed on the basis of a potential difference between two ends of a current sensing resistor which is generated due to an electric current flowing through the H bridge circuit.
However, there is a case where an electric current of several amperes is needed to rotate a motor and when the resistance value of the current sensing resistor is large, power loss in the resistor becomes large. Although it is conceivable to increase the size of the current sensing resistor and to lower the resistance value of the current sensing resistor in order to reduce the power loss, the size of the circuit becomes large in this case.